System of electrical distribution



Ilolodol.)

- v Patentad May l6, I899.

J. B. ENTZ. I

' SYSTEM OF ELECTRICAL DISTRIBUTION.

(Application filed Feb. 6, 1899.)

a the arts.

. UNITED STATES PATENT OFFICE.

JUSTUS n. mm, on PHILADELPHIA, PENNSYLVANIA, ASSIGNOR To THE ELECTRICSTORAGE BATTERY COMPANY, OF NEW JERSEY.

SYSTEM OF ELECTRICAL DISTRIBUTION.

SPECIFICATION forming part of Letters Patent No. 625,100, dated May 16,1899.

Application fil d February a, 1899.. Serial No. 704,628. (N o model-i T0Mitch/0m it may concern/.-

Be it known that I, JUsTUs B. ENTZ, a citizen of the United States,residing at the city of Philadelphia, in the countyofPhiladelphia andState of Pennsylvania, have invented a certain new and useful System ofElectrical Distribution. of which the followingisaspeciilcation.

One objeet of this invention is to supply circuits subjected tofluctuations of load and keep the load on the generator or generatorsconstant, whereby other circuits supplying translating devices requiringsubstantially constant voltage for their practical operation may, ifdesired, be satisfactorily and successin connection with theaccompanying draw-.

ing, forming part hereof, and in which I have illustrateddiagrammatically a system of distribution of my invention.

In the drawing the circuit 1 2 3 is a circuit of varying load. Many suchcircuits occur in the arts; but for the sake of description I willassume that it is a circuit which supplies current to the motors a, thatoperate electric elevators, although it must be borne in mind that itmay be a circuit of any kind that is subjected to fluctuations of load.

4: 5 6 7 is a circuit of constant potential or voltage, such as isfrequently encountered in For the sake of description I will assume itto be a circuit supplying incandescent lamps l), that may be used tolight the building in which the motors a operate the elevators, althoughit must be borne in mind that this circuit may be used for otherpurposes wherc constant voltage is desirable. c is a regulatingbatteryarranged across the leads 2 3 of the circuit, and (Z is a generator orgenerators which supplies current for the system and is in parallel withthe battery. Fluctuations ofload upon the circuit 23, or in the presentinstance upon the elevatormotors a, cause the battery to charge anddischarge, thus varying the voltage or potential of the circuit 2 Tokeep the voltage or potential of the circuit 4 5 constant is one of thefeatures of the invention, and at the same time it is necessary tocharge the battery 0 from the generator cl. To do this, a predeterminedamount of current is supplied at all times during operation to thebattery 0 fromthe generator (l. Since charge and discharge of thebattery 0 in respect to the circuit 2 3 vary itsvoltage, it follows thatmeans must be provided for keeping constant the amount of currentdelivered from the generator d to the battery. These means comprise adynamo-electric machine e, operated at approximately uniform speed andhaving a constantly-excited field-Winding e, which tends to produce inthe armature of the machine e a voltage which will cause current to passfrom the circuit 4 5 of constant potential to the circuit 2- 8 ofvarying potential. This machine is sometimes,hereinafter referred to asa booster. As shown, this field c is constantly excited by way ofconductors S 9, in which there may be interposed a rheost-at e forpurposes of adjustment. The machine e is also provided with a seriesfield e opposing the constantly-excited field e, so that when thecurrent through the series field reaches the predetermined value whichcorresponds to the current that is to be constantly supplied to thebattery it neutralizes the effect of the constantly-excited field e andprevents increase in current by reversing the polarity of thedynamo-electric machine 6, and thus tends to cause current to flow inthe'opposite direction. As shown, the series field e is interposed inone of the leads. For the sake of explanation it may be assumed that nocurrent is being used in the circuit 2 3 and that the apparatus isdesigned to supply at all times a practically constant current to thebattery 0. Under these circumstances the batteryc is being charged bythe generator (1. Its voltage therefore tends to rise, which would havethe efiect to 2 scarce diminish the predetermined -constant currentliiovuever, the effect of this tendency toward decreased. current is toWeaken the series coil e arid thereby diminish itsopposing effect uponthe ccustantly'excited coil e, and thus cause the booster e to build upin voltage suffieieutiy to offset the rise in voltage of the battery incharging and to, as it were, drive enough current to the battery toinsure the re delivery thereto of practically the-predetermined current.Should a sudden and considerable demand be made upon the circuit 2 3orfupon the elevator-motors thereiu, the cattery c willtend todischarge, and therefore to decrease in voltage. This change in voltagewould, it unrestrained, cause current in excess of the predeterminedquantity to from the machined to the battery 0; but the change incurrent also causes the series coil 5 to increase in strength, therebyopposing in greater degree the constantly-ex cited coil c, and thuscausing the booster to decrease or reverse in voltage suliiciently toeorcg eusate for the fall in voltage of the battery and to prevent thepassage of such or? c sof current from the generator (Z to the Eur thesake of explanation I may vrjthat the difierentially'mound booster eoperates with the? rest of the described sys item. to automaticallyprevent more or -less a predetermined quantity of current arrow limitsfrom passing; from the @cr to the battery, so that fluctuations w I fthe booster is that a change in 'curthrough the ho sterautomaticallyeffects ,a change of voltag' of the booster, which rejsistschange of current, whereby a change he cause which results in this operof relative voltage between the generator cl and battery 0, which wouldotherwise cause a great change or even reversal of currentflowinghetweeu the two, is limited to a comparatively small amount. v

it will be obvious to those skilled in the art to which my inventionappertains that modifications may be made in details without departingfrom the spirit thereof. Hence I do not limit myself to the preciseconstruction and arrangement of parts hereinab'ove set forth, andillustrated in the-accompanying drawings; but,

iaviilg thus describedthe nature and objects of my invention, What Iclaim as new, and desire tosecure by Letters Patent, is

1. The combination in asystem of electrical distribution, of, a Workingcircuit, a generator and a battery each arranged across the leadsthereof, and a difterentially-wouud dynamoelectric machine interposed inthe circuit between the generator and battery, substantially asdescribed, 7

2. Means for causing a practically-coustant rate of current to iio'wbetween circuits between which there is a varying difference in voltagewhich comprise a dynamo'electric machine-interposed between saidcircuits and having a constantlyexcited field and a series fieldopposing the constantly-excited field,

substantially as and for the purposes (lo-- scribed.

in testimony whereof I have hereunto signed my name in the presence oftwo wit- IIGSSGS- I JUSTUS B. ENTZ.

Witnesses:

ALFRED J. "Wrnmusou, "W.]F. JACKSON.

